1. Technical Field
The invention relates generally to devices known as xe2x80x9csmart cardsxe2x80x9d and, more particularly to a system, apparatus and method related to power supplies for contactless smart cards.
2. Description of Related Art
A smart card is a xe2x80x9ccredit cardxe2x80x9d sized card that contains electronics. Some cards include a microprocessor and a memory while some cards contain a battery and others do not. The smart card can be used to store large volumes of data. Smart cards are generally tamper-resistant hardware devices and can store private keys and other sensitive information making them ideal for data security applications. Contactless cards, which do not require physical contact between the card and a device used to read it, wirelessly transact information and thus avoid the problem of wear and tear, a problem that afflicts traditional credit cards. For example, embossed numbers on the front and magnetic strips on the back of general purpose credit cards suffer from wear and tear, which can eventually render the card unusable for its intended purpose. Smart cards may be simple memory cards with hardwired logic or may contain a microprocessor. As smart card technology continues to evolve, new and specialized versions of it will continue to be developed. Memory based cards merely store information or values, such as debit or credit information, for example. Microprocessor based cards, on the other hand, can perform calculations, including complex processing and can be used in security applications. Unlike contactless cards, contact cards rely on a physical electrical contact and read information when the card is inserted into a smart card reader. Combination cards can utilize both a contact and a contactless card reader. Harry Newton, Newton""s Telecom Dictionary, Miller Freeman, Inc., Secaucus, N.J. (1999), p. 721.
The electronic device embedded within the smart card is generally some type of integrated circuit chip. In addition to the integrated circuit, the smart card can generally be formed with or without a magnetic stripe and can include an electronic contact module for supporting the electrical contacts to the integrated circuit. The smart card can store and transact information between the card and various other devices, such as for example, a smart card reader. Furthermore, the smart card can provide memory storage as well as computational capability depending on the particular application. The integrated circuit employed in a smart card can be, for example, a microprocessor with internal memory or a memory chip. At one end of the sophistication scale a smart card simply provides memory for storing an identification code while, at the other end of the scale, a smart card provides the computational capacity of a general purpose computer that includes a Central Processing Unit (CPU), Input/Output (I/O) control, Read Only Memory (ROM), Non-Volatile Memory (NVM) and Random Access Memory (RAM). Key applications for smart cards commonly include user identification, transportation, telephone, banking, healthcare, debit purchasing, entertainment, loyalty programs, e-commerce, securing information, telecommuting and networking, campus badging and access, and many other applications which are limited only by the developer""s imagination.
As discussed hereinbefore, there are various types of smart cards designed for a specific application. Smart cards also generally include contact and contactless types. A contact type smart card includes an integrated circuit that communicates directly by way of a physical electrical connection to a reader. The contact type smart card typically includes a gold plated conductive contact module that is provided on a front surface of the smart card. The contact smart card requires the user to insert the card into a smart card reader. Inside the smart card reader, the gold plated conductive contact module makes a direct physical electrical connection to electrical contacts provided within the reader. Information including commands, data, algorithms and card status stored within the smart card are then transmitted through the physical connection.
A contactless type smart card includes an integrated circuit that communicates remotely, or wirelessly, by way of an electromagnetic interface when the smart card is placed in proximity of the card reader. The contactless xe2x80x9cproximityxe2x80x9d smart card utilizes an internal antenna and an electromagnetic signal for transmitting information between the smart card and the reader. Accordingly, the contactless card need only be placed in proximity of the reader, for example within two to three inches of the reader, in order to get energized and begin a transaction.
Contactless smart cards come in passive and active varieties. Passive contactless cards are generally non-battery-powered and must derive the energy to power the integrated circuit from an external electromagnetic field generated by the reader. One drawback of the passive contactless smart card is that only a limited amount of power can be transmitted from the reader. However, passive contactless smart cards can be made having the same thickness as standard sized credit cards because there is no need to provide a bulky battery within the smart card body. Active contactless smart cards generally include a battery within the plastic card body itself in order to provide additional power to the transmitter. However, because batteries are relatively bulky (i.e., even thin watch batteries are several times thicker than a standard credit card), the active contactless cards cannot be made having the same thickness of a credit-card style smart card and are much thicker in order to accommodate the battery.
There are, however, two additional categories of smart cards that are derived from the contact and contactless family. Namely, these smart cards are combination cards and hybrid cards. Combination cards generally include a single integrated circuit having both a contact module and a contactless interface, either of which can communicate between the integrated circuit and the smart card reader. Hybrid cards, on the other hand, include two separate integrated circuits and are sometimes referred to as dual-chip cards. The integrated circuits in a hybrid card include respective contact and contactless interfaces, but the two integrated circuits are not connected to each other within the smart card.
Smart cards are also categorized according to the type of integrated circuit used in the smart card. For example, there are smart cards that include a memory chip and there are smart cards that include either a microprocessor or a micro-controller. Smart cards having only memory chips are merely storage devices and do not have any computational capability. Their function is similar to a floppy disk that can store anywhere from a few bits to a few thousand bits. For example, memory smart cards generally store between 103 and 16,000 bits of data. Memory smart cards are less expensive than microprocessor cards but lack the sophistication of data security, data management and computational capabilities.
Alternatively, microprocessor or micro-controller based smart cards are much more sophisticated and are capable of managing data stored in its memory circuits. For example, these smart cards can edit and otherwise manipulate the data stored in its memory circuits. The computational functionality of microprocessor-based smart cards also includes the ability of managing complex algorithms. Such smart cards are really miniature computers that include microprocessors having 8, 16 or 32 bit architectures with data storage capacity ranging from 300 bytes to 32,000 bytes. However, increased computing power and storage capacity can be expected with future development and advances in semiconductor technology.
Contactless proximity smart cards require electrical power in proportion to the amount of data that is to be transmitted from the smart card. In order to transmit large amounts of data, active contactless proximity smart cards have included an internal battery. As discussed above, the draw back of this approach is that the smart card body must be made larger than the standard credit card size in order to accommodate the battery. Standard non-battery contactless smart cards (i.e., passive smart cards) are incapable of transmitting large amounts of data because they receive a limited amount of energy from the electromagnetic signal transmitted by the card reader. Therefore, there is a need in the art to provide electrical power from an external power supply other than the card reader to a non-battery contactless smart card. The additional power would facilitate the transmission of large amounts of data. Nevertheless, there is also a need to maintain the physical size of the contactless proximity card to a standard xe2x80x9ccredit cardxe2x80x9d size as specified in ISO Standard 7816, which is herein incorporated by reference in its entirety.
Furthermore, there is a need in the art to provide a system wherein the operation of a vehicle, or other kinds of equipment, is controlled by way of an authorization code such that only authorized users can access the vehicle and the other kinds of equipment without fumbling with keys or pressing buttons on wireless transmitters. There is also an interest in providing society with the benefits of a more effective way of preventing vehicle thefts by restricting the operation of vehicles and other forms of equipment utilizing authorization codes.
Moreover, contact smart cards having chip contact modules on a front portion of the card body take up valuable surface area that can be used for printed material. Therefore, there is a need for a smart card wherein the entire surface area of the front portion, or top side, of the card body can be utilized for personalized graphics, alphanumeric symbols, pictures, art-work and other indicia or printed material on.
Yet, there is still a need in the art for a smart card having an optical communication interface. Therefore, there is a need for providing a smart card using an optical interface for communicating information between the smart card and a reader.
According to one embodiment, the present invention is directed to a system for providing an external electrical power supply to a smart card for driving internal electronics of the smart card wherein the external electrical power supply is separate from a power supply of a smart card reader or an internal battery.
Accordingly, one aspect of the invention provides a power supply that includes a battery; an oscillator in communication with the battery; and an antenna coupled to the oscillator. The power supply also includes a first amplifier in communication with the oscillator and in one embodiment the first amplifier is coupled to the antenna. Further, in one embodiment the oscillator produces a signal having a frequency that ranges from about 10 MHz to about 14 MHz. The power supply also a card retainer affixed to the power supply and in one embodiment the card retainer is a clip. The power supply also includes a first switch in communication with the battery; a second amplifier coupled to the antenna; and a logic circuit for controlling the power supply. Still further, in one embodiment the power supply includes a second amplifier coupled to the antenna; and a logic circuit in communication with the second amplifier; wherein the logic circuit controls the power supply according to a signal received by the second amplifier through the antenna. In one embodiment the power supply also includes a first switch in communication with the logic circuit, wherein the first switch controls the power supply. The power supply also includes a latch for receiving a smart card and the latch further comprises a second switch, wherein when the smart card is received by the latch, the second switch enables the power supply to be operated.
Another aspect of the invention provides a smart card power supply system that includes a smart card having an antenna for receiving electromagnetic energy; and a portable power supply electromagnetically communicating with the smart card; wherein the portable power supply generates electromagnetic energy for energizing the smart card. In one embodiment the smart card is a contactless smart card and in another embodiment the smart card is a combination smart card. The system further includes a smart card reader including a power supply electromagnetically coupled to the smart card and in one embodiment the smart card is energized from a combination of the smart card reader power supply and the portable power supply. In another embodiment the portable power supply further includes a latch for receiving a smart card wherein the portable power supply is enabled when the smart card is received by the latch. In yet another embodiment the portable power supply is enabled upon receiving an external electromagnetic signal. Still in another embodiment a smart card reader generates the external electromagnetic signal.
A further aspect of the invention includes a method of supplying power to a smart card that includes generating a first electromagnetic signal having a first frequency; and transmitting the first electromagnetic signal to a smart card tuned to the first frequency. In one embodiment the method includes receiving a second electromagnetic signal; and enabling the transmission of the first electromagnetic signal upon receiving the second electromagnetic signal. In yet another embodiment the method includes enabling the transmission of the first electromagnetic signal upon receiving a signal from a switch contact closure.
These and other inventions will be apparent from the detailed description hereinafter.